Genetic and ecologic characteristics of Bartonella communities in rodents in southern China

Ecologic and bacteriologic observations of small mammals captured in Yunnan Province in the People's Republic of China indicated that Bartonella infections occurred at a high prevalence among some rodent species. Sequence analyses of the citrate synthase genes of these Bartonella demonstrated that rodents in this region harbored a diverse assemblage of strains. The Bartonella isolates obtained from Apodemus, Eothenomys, and Rattus typically clustered separately by genus of rodent host. Cultures obtained from Rattus rats were genetically related to Bartonella elizabethae, a recognized human pathogen. The finding of Bartonella species in a high proportion of the rodent samples from Yunnan suggests the need to investigate whether these agents might be responsible for cases of febrile illnesses of unknown etiology in southern China and elsewhere in southeastern Asia.     

首次证实巴尔通体在我国云南鼠群中流行

目的　了解巴尔通体 (Bartonella)在云南鼠群中的分布及流行特征。方法　被检鼠血为 1999年 10月收集自云南省的 3个调查地区 ,采用兔血心浸液琼脂培养基进行巴尔通体分离 ,以聚合酶链反应 (PCR)对枸橼酸合酶基因 (gltA)的379bp片段进行扩增以证实是否巴尔通体 ,阳性者行以序列测定并与已知菌株加以比较。 结果与结论　从 131份鼠血分离到5 8株巴尔通体 (44 3% )。菌株分布于各调查点 ,感染鼠分属 3个属 6个种 ,以姬鼠属 (Apodemus)的带菌率最高 (6 2 2 % ,2 8/4 5 ) ,家鼠属 (Rattus)次之 (41 5 % ,2 7/ 6 5 ) ,绒鼠属 (Eothenomys)居第三位 (18 8% ,3/ 16 ) ,表明巴尔通体在云南常见鼠种中广泛分布及高度流行。所有菌株按其分离鼠属可分为 3群 ,具有以属为水平的宿主特异性。依基因结构可将它们分为 2 0个变异体 (家鼠属 8个 ;姬鼠属 12个 ;绒鼠属 2个 ) ,其中 17个为新发现变异体 ,表明云南巴尔通体基因型别的多样性。 7个家鼠巴尔通体变异体可分为B elizabethae、B tribocorum和新种B yunnannensis 3个基因型。由于云南巴尔通体的高度流行及基因型别的多样性 ,一些不明原因的疾病可能与巴尔通体的感染有关。需要对该地区巴尔通体的流行情况及对人类致病作用进行系统的调查和研究     

Rats of the genus Rattus are reservoir hosts for pathogenic Bartonella species: an Old World origin for a New World disease?

Bartonella species were isolated from the blood of 63 of 325 Rattus norvegicus and 11 of 92 Rattus rattus from 13 sites in the United States and Portugal. Infection in both Rattus species ranged from 0% (e.g., 0/87) to approximately 60% (e.g., 35/62). A 337-bp fragment of the citrate synthase (gltA) gene amplified by polymerase chain reaction was sequenced from all 74 isolates. Isolates from R. norvegicus were most similar to Bartonella elizabethae, isolated previously from a patient with endocarditis (93%-100% sequence similarity), followed by Bartonella grahamii and other Bartonella species isolated from Old World rodents (Clethrionomys species, Mus musculus, and Rattus species). These data suggest that Rattus species are a reservoir host for pathogenic Bartonella species and are consistent with a hypothesized Old World origin for Bartonella species recovered from Rattus species introduced into the Americas.     

Bartonella species in small mammals and their ectoparasites in Taiwan

Bartonella spp. prevalence in small mammals and their ectoparasites was investigated in Taiwan. Blood samples were obtained from 66 rats, 20 shrews, 276 mites (Laelaps spp.), 74 fleas (Xenopsylla cheopis), 81 lice (Polyplax spp.), and 47 ticks (41 Dermacentor spp. and 6 Ixodes spp.). Bartonellae were isolated or detected in 27 (31.4%) animals. Bartonella DNA was detected in 48 (64.9%) fleas and 11 (64.7%) pooled lice samples, but not in mite and tick samples. Bartonella phoceensis, B. queenslandensis, B. tribocorum, B. elizabethae, and B. rattimassiliensis were isolated or detected in bacteremic mammals. For the first time in Taiwan, B. tribocorum, B. elizabethae, B. queenslandensis, and a B. rochalimae-like strain were detected in fleas, and B. tribocorum, B. phoceensis, and B. rattimassiliensis were detected in lice obtained from small mammals. A broader range of Bartonella species was identified in the ectoparasites than in the small mammals.     

Prevalence and diversity of Bartonella in rodents of northern Thailand: a comparison with Bartonella in rodents from southern China

We report results of the first study to investigate the distribution and diversity of Bartonella in rodents from Thailand. Whole blood from 195 rodents, representing six species, was tested for the presence of Bartonella species using standard culture techniques. Isolates were obtained from 17 (8.7%) of the samples, and 14 of those isolates represented distinct strains, based upon partial sequencing of the citrate synthase (gltA) gene. Phylogenetic analysis of the isolates and other Bartonella species indicated that five unique isolates from Bandicota indica form a cluster that may represent a new Bartonella species. Two additional isolates from B. indica clustered together, and were nearly identical to an isolate from Apodemus draco collected in southern China. Importantly, a number of the isolates from Thailand rodents are closely related to B. grahamii and B. elizabethae, species which have been associated with human illness.     

Surveillance of Egyptian fleas for agents of public health significance: Anaplasma, Bartonella, Coxiella, Ehrlichia, Rickettsia, and Yersinia pestis

Serologic surveys in Egypt have documented human and animal exposure to vector-borne bacterial pathogens, but the presence and distribution of these agents in arthropods has not been determined. Between July 2002 and July 2003, fleas were collected from 221 mammals trapped in 17 cities throughout Egypt. A total of 987 fleas were collected, representing four species (Ctenocephalides felis, Echidnophaga gallinacea, Leptopsylla segnis, and Xenopsylla cheopis); 899 of these fleas were X. cheopis from rats (Rattus spp.). Fleas were tested for DNA from Anaplasma spp., Bartonella spp., Coxiella burnetii, Ehrlichia spp., Rickettsia spp., and Yersinia pestis. Rickettsia typhi, the agent of murine typhus, was detected in X. cheopis and L. segnis from rats from nine cities. A spotted-fever group Rickettsia sp. similar to "RF2125" was detected in E. gallinacea, and two unidentified spotted fever group Rickettsia were detected in two X. cheopis. Novel Bartonella genotypes were detected in X. cheopis and L. segnis from three cities. Coxiella burnetii was detected in two fleas. Anaplasma, Ehrlichia, and Y. pestis were not detected.     

浙江省鼠形动物巴尔通体的遗传进化分析

目的分析浙江省鼠形动物中巴尔通体分子遗传进化关系,为巴尔通体人群感染的预防控制提供科学依据。方法用夹夜法在浙江省不同地区、不同季节捕获鼠形动物,无菌操作取鼠肝和脾,用PCR和分离培养检测巴尔通体,对部分阳性产物测序,提交到GenBank,用CLUSTAL W进行匹配,然后用PAUP4.0beta10软件构建系统关系,分析其遗传进化关系。结果我们分别从黑线姬鼠、黄毛鼠、褐家鼠、黑腹绒鼠、社鼠、臭鼩鼱、东方田鼠、黄胸鼠和大林姬鼠中检测到巴尔通体特异DNA片段,浙江首次从黑线姬鼠脾中分离出一株巴尔通体。遗传进化分析显示我们检测到的巴尔通体与Bartonellaratti massiliensis以及对人类有致病性的B.grahamii的遗传关系最近。结论浙江省鼠类中广泛存在巴尔通体感染,而且携带人类致病性巴尔通体,存在人群感染风险。     

江西省部分地区鼠形动物中巴尔通体分布及基因组序列研究

目的 了解江西省鼠形动物中巴尔通体的携带状况和基因型特征,为巴尔通体感染的疾病预防控制提供科学依据.方法 2018-2019年在南城县、广信区、横峰县、广丰区、铜鼓县5个鼠传疾病监测项目点,采集130只鼠形动物的肝、脾组织标本进行巴尔通体分离培养,挑取形态疑似巴尔通体的菌落纯培养后提取核酸,PCR检测巴尔通体属特异性基...     

巴尔通体在厦门市鼠形动物间及各区域间的分布

目的掌握厦门地区鼠形动物巴尔通体流行情况,证实厦门市鼠形动物感染巴尔通体菌属,为控制人巴尔通体流行提供参考依据。方法根据厦门市行政区划和地理状况划片,随机抽取3个不同区作为调查点。在不同生境采用笼日法捕鼠,取血,用细胞培养法分离巴尔通体;PCR扩增细菌gltA基因片段（376 bp）,并进行序列分析,寻查本地巴尔通体属种。结果厦门市以褐家鼠为巴尔通体主要宿主动物（51.21%）,其次为臭鼩鼱（29.09%）、黄胸鼠（16.36%）及小家鼠、黑家鼠和黄毛鼠等（3.33%）。3个区共采集鼠形动物血样330份,培养分离出巴尔通体84株,感染率25.45%,其中以臭鼩鼱感染率最高,为32.29%,黄胸鼠为24.07%、褐家鼠为23.08%;各调查点鼠形动物巴尔通体感染率分别为：湖里22.64%,海沧28.68%,同安24.51%,差异无统计学意义（P〉0.05）。查出的巴尔通体分别为B.elizabethae、B.queenslandensis和B.tribocorum,其中B.tribocorum分为A、B两群,B群仅感染臭鼩鼱。结论厦门市鼠形动物巴尔通体感染普遍,且存在宿主多样性和菌株对宿主的选择性。     

Ixodes ricinus is not an epidemiologically relevant vector of Bartonella species in the wood mouse (Apodemus sylvaticus)

Bartonella are hemoparasites exploiting a range of mammals as reservoir hosts. Several species are zoonotic pathogens. Fleas, lice, and other arthropods, such as ticks, have been implicated as vectors. While the competence of ticks as vectors of Bartonella species has recently been demonstrated, the epidemiological significance of ticks as vectors of Bartonella species in wildlife populations remains unknown. We used the presence of deer at study sites to control the presence of Ixodes ricinus ticks, and used this system to determine whether I. ricinus contributes to the epidemiology of Bartonella species infections in small mammals. Ticks were present at all sites with deer, but were absent from all sites without deer; however, the abundance of ticks on small mammals did not affect the probability of wood mice being infected with Bartonella species. Data presented here indicate that I. ricinus is not involved in the transmission of Bartonella in woodland rodents.     

云南省泸西县啮齿动物携带立克次体调查

目的 调查云南省泸西县啮齿动物携带恙虫病东方体、无形体和埃立克体的状况,了解该类病原体在当地自然界中的保存状况和基因特征。方法 用鼠笼和鼠夹在云南省泸西县捕鼠,将捕获的动物种类鉴定后解剖取脾脏,活鼠取血。采用巢式PCR扩增脾脏的恙虫病东方体groEL基因,无形体和埃立克体的16S rRNA基因特异片段;测定PCR扩增阳性产物的DNA序列,对获得序列进行序列比对和系统进化分析。IFA法检测鼠血清中恙虫病东方体IgG抗体。结果 在泸西县共捕获啮齿动物10种225只。其中黄胸鼠36.89%(83/225)、大绒鼠35.11%(79/225)和中华姬鼠13.78%(31/225)为优势鼠种。获得鼠血清85份。鼠脾脏中检测到5株东方体groEL基因阳性标本,带毒鼠种为黄胸鼠2.41%(2/83)和大绒鼠3.80%(3/79)。同源性比较显示,这5株东方体的相似性在99.02%~100%之间,他们分别与GenBank中已知立克次体序列的相似性在98.75%~100%。系统发生树显示,5株OT与来自日本、泰国和中国安徽的菌株位于同一分支。3份16S rRNA阳性标本,其中1份埃立克体阳性,来源于大绒鼠;1份沃尔巴克氏体和1份巴尔通体阳性均来源于黄胸鼠。无形体均为阴性。埃立克体株序列比对显示与来自美国、中国和巴西的埃立克体基因同源性为98.0%~100%,并与分离自美国野外工作者皮肤的伊文氏埃立克体在同一分支。鼠血清恙虫病IgG抗体阳性7份,阳性率8.24%(7/85)。结论 该地区存在以黄胸鼠和大绒鼠为主要宿主的恙虫病自然疫源地。埃立克体、巴尔通体和沃尔巴克氏体在啮齿动物中也存在感染,需注意防控。     

福建沿海臭鼩鼱感染巴尔通体调查研究

目的证实臭鼩鼱感染巴尔通体,了解其分布,分析菌株基因型,为巴尔通体病的防治提供依据。方法采集福建沿海6地市臭鼩鼱血样,培养分离巴尔通体菌株,PCR扩增病原体gltA基因片段进行序列分析,构建生长发育树,并分析各属种的宿主和地区分布。结果臭鼩鼱占本调查鼠形动物的25.33%,与褐家鼠、黄胸鼠构成了室内鼠形动物优势种群。臭鼩鼱血样中分离并证实63份感染巴尔通体,感染率21.43%(63/294),分布在各调查区域内。臭鼩鼱被B.tribocorum A、B种群感染,A、B群的分布也体现了一定的地域特征。结论臭鼩鼱是B.tribocorum A、B种群的保存宿主,且感染率高、分布广,应加强调查研究。     

Occurrence of ectoparasites on rodents in Sukhothai Province, northern Thailand

A survey of ectoparasites on rodents was carried out bimonthly from April 2008 to March 2009 in 3 districts of Sukhothai Province, northern Thailand. A total of 130 rodents comprising 8 species of hosts were captured and examined for ectoparasites. The hosts examined were Bandicota indica, Bandicota savilei, Rattus losea, Rattus rattus, Rattus exulans, Rattus norvegicus, Menetes berdmorei and Tamiops mcclellandii. Ninety-seven ectoparasites were collected: 1 species of tick (Hemaphysalis bandicota), 2 species of mites (Laelaps nuttali and Laelaps echidninus), and 1 species of flea (Xenopsylla cheopis) were identified. The infestation rates by ticks, mites and fleas on the rodents were 0.77, 5.38 and 6.15%, respectively. Monitoring the rodent population and their ectoparasites is important for future planning of prevention and control of zoonotic diseases in the area.     

Molecular screening of Bartonella species in rodents from south western Spain

Rodents (87 Mus spretus and 10 Rattus norvegicus) collected in a suburban area of Seville (Andalusia, Spain) between September 2003 and April 2004 were tested by polymerase chain reaction for the presence of Bartonella DNA using primers amplifying a fragment of the 16S/23S rRNA internal transcribed spacer (ITS). Sequence analyses of the ITS of these Bartonella demonstrated that rodents in this region harbored at least three strains: two Bartonella genotypes detected in M. spretus, which clustered separately, and one genotype corresponding with B. tribocorum in R. norvegicus. The finding of Bartonella species in a high proportion of the rodent samples suggests the need to investigate whether these agents might be responsible for cases of febrile illnesses of unknown etiology in Southern Spain.     

Identification of Diverse Bartonella Genotypes among Small Mammals from Democratic Republic of Congo and Tanzania

Abstract. Small mammals from the Democratic Republic (DR) of the Congo and Tanzania were tested to determine the prevalence and genetic diversity of Bartonella species. The presence of Bartonella DNA was assessed in spleen samples of the animals by rpoB- and gltA-polymerase chain reactions (PCRs). By rpoB-PCR, Bartonella was detected in 8 of 59 animals of DR Congo and in 16 of 39 Tanzanian animals. By gltA-PCR, Bartonella was detected in 5 and 15 animals of DR Congo and Tanzania, respectively. The gene sequences from Arvicanthis neumanni were closely related to Bartonella elizabethae. The genotypes from Lophuromys spp. and from Praomys delectorum were close to Bartonella tribocorum. Five genogroups were not genetically related to any known Bartonella species. These results suggest the need to conduct further studies to establish the zoonotic risks linked with those Bartonella species and, in particular, to verify whether these agents might be responsible for human cases of febrile illness of unknown etiology in Africa.     

Rodent-associated Bartonella in Saskatchewan, Canada

Six species of wild rodents were sampled at 10 sites in 2002 and 2003 to determine the prevalence of Bartonella infections in rodent communities near Saskatoon, Saskatchewan, Canada. Isolates were characterized genotypically and compared with isolates found at other locations. Of 104 wild rodents examined, 57% were infected with Bartonella and prevalence within species varied from 49% for Richardson's ground squirrels (Spermophilus richardsonii) to 90% for Franklin's ground squirrels (S. franklinii). Infected rodents were found at all sites. Sequencing of a 379-bp portion of the citrate synthase gene was performed on 54 isolates and revealed 13 distinct genotypes, eight of which had not been described previously. The most common genotype detected in red-backed voles (Clethrionomys gapperi) was 99.1% similar to B. grahamii, a known human pathogen. Two of 10 Franklin's ground squirrels were concurrently infected with multiple Bartonella genotypes. All genotypes, with the exception of one detected in both Franklin's and thirteen-lined ground squirrels (S. tridecemlineatus), were found in only one host, and all genotypes from each species, with the exception of genotypes detected in red-backed voles, clustered together within the same relatedness group, suggesting that at least some Bartonella genotypes are specific to some rodent hosts.     

几种鼠类人工感染日本血吸虫的实验观察

对常见的5种野鼠人工感染日本血吸虫尾蚴后,观察野鼠体内的成虫发育率、虫体大小、寄生部位、血清抗体反应及排卵等情况,以了解不同野鼠对血吸虫的易感性。实验结果,野鼠对血吸虫易感性的高低依次为板齿鼠、海南屋顶鼠、黄胸鼠、黄毛鼠、褐家鼠。不同种属的野鼠与血吸虫的关系差异较大,如作为新感染调查对象,应在原螺区内以敏感的优势鼠种为主,才能取得确切的结论。     

Characterization of Bartonella strains isolated from black-tailed prairie dogs (Cynomys ludovicianus)

Thirty bartonella strains were isolated from the blood of black-tailed prairie dogs (Cynomys ludovicianus) from Boulder County, Colorado, USA. The bacteria appeared as small, fastidious, aerobic, Gram-negative rods. The partial sequences of the citrate synthase gene (gltA) demonstrated five unique genetic variants. Phylogenetic analysis based on sequences of gltA, 16S rRNA, rpoB, ftsZ, and ribC showed that the black-tailed prairie dog-related Bartonella variants comprise a distinct monophyletic clade that is closely related to Bartonella washoensis, a species isolated from a human patient and subsequently from ground squirrels. These variants, however, are grouped together in 100% of the bootstrapped trees. These variants were not found in other small mammals trapped during the same study, showing some evidence of host specificity. We believe that the group being described here is typical of the black-tailed prairie dog. We propose to name the bacteria Candidatus Bartonella washoensis subsp. cynomysii. The type strain is CL8606co(T)(=ATCC BAA-1342(T) = CCUG 53213(T)), which is the representative isolate of the dominant variant of the characterized group.     

福建省鼠类感染巴尔通体调查及序列分析

目的了解福建省鼠类中巴尔通体(Bartonellaspp.)的感染状况和基因特征。方法 2014-2016年采用笼日法在福建省闽东、闽西、闽南、闽北和闽中捕鼠,现场鉴定并记录捕获鼠类的釆集时间、地点、鼠种、性别、鼠龄等资料。采集鼠心脏血,PCR扩增巴尔通体的gltA和16S~23SrRNA基因,阳性PCR产物送测序并进行序列比对分析,构建系统进化树。感染率间的比较采用χ~2检验或Fisher精确检验法。结果调查共布放鼠笼5 917笼次,捕鼠381只,鼠密度为6.44%。巴尔通体感染率为12.34%。家鼠的巴尔通体感染率为10.61%,褐家鼠(Rattus norvebicus)和黄胸鼠(Rattus flavipectus)感染率分别为11.30%和10.00%;野鼠的感染率为13.86%,黄毛鼠(Rattus losea)和针毛鼠(Rattus fulvescens)感染率分别为22.86%和18.00%,野鼠的巴尔通体感染率高于家鼠的感染率,但无统计学意义。从地区分布看,闽西、闽北一带的感染率较高,分别为20.00%和25.33%。闽南一带感染率最低,为0。各地区感染率存在统计学意义(P0.05)。不同性别、鼠龄的巴尔通体感染率差异无统计学意义,而不同的生境下的感染率存在统计学差异(P0.05)。阳性样本测序分析显示,福建省鼠类感染的巴尔通体序列与B.tribocorum、B.elizabethae和B.grahamii序列最接近。结论福建省鼠类存在巴尔通体感染,存在对人群致病的风险。     

Urban zoonoses caused by Bartonella,Coxiella, Ehrlichia,and Rickettsia species

The last half of the 20th Century witnessed an increase in the occurrence and recognition of urban zoonoses caused by members of the genera Bartonella, Coxiella, Ehrlichia, and Rickettsia, all traditionally considered to be members of the family Rickettsiaceae. In recent years, new human pathogens (Bartonella elizabethae, Bartonella henselae, and Rickettsia felis) have been recognized in urban environments. Other newly recognized pathogens (Ehrlichia chaffeensis and Ehrlichia phagocytophila in the United States) have sylvan zoonotic cycles but are present in urban areas because their vertebrate hosts and associated ectoparasitic arthropod vectors are able to survive in cities. Still other agents, which were primarily of historical importance (Bartonella quintana) or have not traditionally been associated with urban environments (Rickettsia rickettsii), have been recognized as causes of human disease in urban areas. Some diseases that have traditionally been associated with urban environments, such as rickettsialpox (caused by Rickettsia akari) and murine typhus (caused by Rickettsia typhi), still occur in large cities at low or undetermined frequencies and often go undetected, despite the availability of effective measures to diagnose and control them. In addition, alternate transmission cycles have been discovered for Coxiella burnetii, Rickettsia prowazekii, and R. typhi that differ substantially from their established, classic cycles, indicating that the epidemiology of these agents is more complex than originally thought and may be changing. Factors leading to an increase in the incidence of illnesses caused by these bacteria in urban areas include societal changes as well as intrinsic components of the natural history of these organisms that favor their survival in cities. Transovarial and transstadial transmission of many of the agents in their arthropod hosts contributes to the highly focal nature of many of the diseases they cause by allowing the pathogens to persist in areas during adverse times when vertebrate amplifying hosts may be scarce or absent. Domesticated animals (primarily cats, dogs, and livestock) or commensal rodents [primarily Norway rats (Rattus norvegicus) and house mice (Mus musculus)] can serve as vertebrate amplifying hosts and bring these agents and their ectoparasitic arthropod vectors into direct association with humans and help maintain transmission cycles in densely populated urban areas. The reasons for the increase in these urban zoonoses are complex. Increasing population density worldwide, shifts in populations from rural areas to cities, increased domestic and international mobility, an increase in homelessness, the decline of inner-city neighborhoods, and an increase in the population of immunosuppressed individuals all contribute to the emergence and recognition of human diseases caused by these groups of agents. Due to the focal nature of infections in urban areas, control or prevention of these diseases is possible. Increased physician awareness and public health surveillance support will be required to detect and treat existing urban infections caused by these agents, to determine the disease burden caused by them, to design and implement control programs to combat and prevent their spread, and to recognize emerging or resurging infections caused by members of these genera as they occur.